Acute dengue virus 2 infection in Gabonese patients is associated with an early innate immune response, including strong interferon alpha production

<p>Abstract</p> <p>Background</p> <p>Dengue is now a leading cause of morbidity and mortality throughout the tropics. We conducted the first <it>ex vivo </it>study of dengue fever (DF) in African patients infected during the first Gabonese dengue virus 2 (DENV-2) outbreak in 2007, in order to investigate cytokine production, including the antiviral cytokine IFN-α, reported to be a potent inhibitor of DENV replication <it>in vitro</it>.</p> <p>Methods</p> <p>Levels of 50 cytokines, chemokines and growth factors were measured in plasma from 36 patients with DENV-2 infection, and in uninfected controls, using Luminex multiplex technology. The results were interpreted according to the day of sampling after symptom onset. PBMC from six patients were also studied for T lymphocyte cell surface marker expression by flow cytometry.</p> <p>Results</p> <p>Acute DENV-2 infection elicited high levels of several pro-inflammatory cytokines (IL-6 and IL-17), chemokines (MIF, RANTES, IP-10 and MCP-1) and growth factors (G-CSF, GM-CSF and VEGF-A). We also observed high levels of IFN-α for the first time in adult DF patients, and CD4+ and CD8+ T cell activation at symptom onset.</p> <p>Conclusion</p> <p>Acute DENV-2 infection in African patients elicits a strong innate response involving IFN-α production, as well as an adaptive immune response.</p

Concurrent Chikungunya and Dengue Virus Infections during Simultaneous Outbreaks, Gabon, 2007

An outbreak of febrile illness occurred in Gabon in 2007, with 20,000 suspected cases. Chikungunya or dengue-2 virus infections were identified in 321 patients; 8 patients had documented co-infections. Aedes albopictus was identified as the principal vector for the transmission of both viruses

High Prevalence of Respiratory Viral Infections in Patients Hospitalized in an Intensive Care Unit for Acute Respiratory Infections as Detected by Nucleic Acid-Based Assays

Forty-seven bronchoalveolar lavages (BAL) were obtained from 41 patients with acute pneumonia attending an intensive care unit. By molecular diagnosis, 30% of total BAL and 63% of bacteria-negative BAL were positive for respiratory viruses. Molecular detection allows for high-rate detection of respiratory viral infections in adult patients suffering from severe pneumonia

Comparison of Washing and Swabbing Procedures for Collecting Genital Fluids To Assess Cervicovaginal Shedding of Herpes Simplex Virus Type 2 DNA

Asymptomatic genital shedding of herpes simplex virus type 2 (HSV-2) DNA was evidenced by real-time PCR in 25 (13.2%) of 188 cervicovaginal lavage samples and in only 13 (6.9%) paired cervicovaginal samples from 188 HSV-2-seropositive, nonpregnant childbearing-aged human immunodeficiency virus-seronegative women living in Gabon. These observations demonstrate that cervicovaginal washing is more suitable than endocervicovaginal swabbing for detecting and quantifying HSV-2 DNA by PCR in female genital secretions

Seroprevalence and HCV RNA by gender, age group, ART treatment, CD4+ T cells and HIV-VL groups.

<p>Seroprevalence and HCV RNA by gender, age group, ART treatment, CD4+ T cells and HIV-VL groups.</p

Low prevalence of HCV infection with predominance of genotype 4 among HIV patients living in Libreville, Gabon

<div><p>Background</p><p>Gabon is an endemic area for human immunodeficiency virus (HIV) and hepatitis C virus (HCV) and the risk of co-infection is high.</p><p>Method</p><p>Between November 2015 and April 2016, we conducted retrospective study on HCV infection among people living with HIV/AIDS (PLHA). A total of 491 PLHA were included in this study and tested for the presence of HCV infection. HIV viral loads were obtained using the Generic HIV viral Load® assay and the CD4+ T cells count was performed using BD FACSCount™ CD4 reagents. HCV screening was performed using the MP Diagnostics HCV ELISA 4.0 kit. HCV genotypes were determined by sequence analysis of NS5B and Core regions. The Mann-Whitney test was used to compare the groups. Chi-2 test and Fisher's Exact Test were used to compare prevalence.</p><p>Results</p><p>HCV seroprevalence was 2.9% (14/491), (95% confidence interval (CI):1.4–4.3%). The percentage of HCV viremic patients, defined by the detection of HCV RNA in plasma, was 57% (8/14), representing 1.6% of the total population. HCV seroprevalence and replicative infection were not statistically differ with gender. The percentage of co-infection increased with age. No correlation with CD4+ T cells count and HIV viral load level was registered in this study. Identified HCV strains were predominantly of genotype 4 (87.5%) including 4k, 4e, 4g, 4p, 4f and 4c subtypes. Only one strain belonged to genotype 2 (subtype 2q). Analysis of the NS5B region did not reveal the presence of resistance-associated substitutions for sofosbuvir.</p><p>Conclusion</p><p>A systematic screening of hepatitis C is therefore strongly recommended as well as genotyping of HCV strains in order to adapt treatments for the specific case of people living with HIV/AIDS in Central Africa.</p></div

Seroprevalence and HCV RNA by gender, age group, ART treatment, CD4+ T cells and HIV-VL groups.

<p>Seroprevalence and HCV RNA by gender, age group, ART treatment, CD4+ T cells and HIV-VL groups.</p

Phylogenetic analysis of HCV Core sequences.

<p>Neighbor-joining phylogenetic tree constructed with our sequences and reference sequences for HCV genotypes retrieved from the Gen-Bank. The Kimura two-parameter method of estimating genetic distance was used. Numbers next to the nodes of the tree represent bootstrap values (1000 replicates). Branches for genotype 4 are indicated in red and in green for genotype 2. Our sequences are preceded by a spot. The Gen-Bank accession numbers of the new core sequences of HCV are KY661736 to KY661743.</p